Recent research on Marfan Syndrome has centered on linkage analysis and on the cell biology and biochemistry of affected cells and tissues. Both approaches are producing exciting results. Intensive linkage studies have considerably narrowed the number of possible chromosomal locations, and linkage to chromosome 15 markers has been reported at meetings. The progress in this area is rapid and the various laboratories pursuing this approach should be brought together to combine their data and to evaluate the present status of the Marfan linkage map. At the same time, cell biology studies have shown that there is a considerable reduction in fibrillin staining in the matrix produced by cultured cells from some MS patients, and that this abnormality is inherited in a Mendelian fashion in affected families. These results suggest that the fibrillin gene, or a gene for another protein associated with the microfibrils, should be regarded as strong candidates for the Marfan mutation. There is a clear perception on the part of scientists involved with research on Marfan Syndrome that the time is right for a wide-ranging review of both the genetic and biochemical aspects of Marfan Syndrome. The proposed meeting will be for two days and amongst the topics to be discussed are: a review of the diagnostic criteria for Marfan Syndrome and related phenotypes, and a discussion of whether these need to be redefined; an evaluation of all those studies purporting to find abnormalities in extracellular matrix components; a critical review of the latest findings of linkage of Marfan Syndrome with markers, both candidate gene probes and anonymous probes; a discussion of the best way to utilize scarce resources, and how to encourage further collaboration between laboratories. We believe that by bringing together scientists from different areas of research, new ideas for further experimentation will be generated that will speed the task of finding the genetic and physiological basis for the disease.